1. Field of the Invention
The present invention relates to a liquid crystalline compound having two epoxy groups or oxetane groups as a polymerizable functional group and having a fluorene ring in a skeletal structure, a composition containing the same, a polymer thereof and uses thereof.
2. Related Art
When a polymerizable liquid crystal compound aligned in a nematic state is polymerized, a molded article which is fixed in an aligning state to have an optical anisotropy is obtained. A molded article having an optical anisotropy is actively used as an optical compensation film for a liquid crystal display element. A compound having an acryl group as a polymerizable group is used as a polymerizable liquid crystal compound.
When producing an optical compensation film, a polymerizable liquid crystal composition containing a suitable photopolymerization initiator is first coated on a substrate such as triacetyl cellulose (hereinafter abbreviated as TAC) subjected to aligning treatment. Next, it is irradiated with an electron beam such as a UV ray and polymerized to obtain an optically anisotropic film in which alignment of the liquid crystal is fixed (refer to patent document 1 and patent document 2).    Patent document 1: JP H13-55573 A/2001    Patent document 2: JP H13-154019 A/2001
The following three conditions are desired in a step of irradiating with a UV ray.    Curing at a room temperature without requiring a specific heating device.    Curing in the air without requiring substitution with an inert gas such as nitrogen.    Curing in a UV ray-irradiating time of several seconds.
When a conventional acryl base polymerizable liquid crystal material is used to produce an optically anisotropic film by the production process described above, the following two problems are involved therein:
When the material is cured in the air with a UV ray, it is inhibited from being cured by oxygen-containing air, and a cured film is not obtained.
The cured optically anisotropic film is peeled off from TAC because of a weak adhesive strength thereof with TAC which is a substrate of the film.
A polymerizable liquid crystal compound which can solve the above various problems and a composition containing the same are desired.